由于我使用的是一些较老的第三方代码,我编译了boost::system
和boost::serialization
与旧的GCC ABI(https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html)。冲突的升级版本
,我把它们内置到已被设置为链接的有效路径/usr/local/lib
(我用到其他库有作为),并将其重命名为:
$ ls /usr/local/lib/libboost_*
/usr/local/lib/libboost_serialization_old_abi.so
/usr/local/lib/libboost_serialization_old_abi.so.1.60.0
/usr/local/lib/libboost_system_old_abi.so
/usr/local/lib/libboost_system_old_abi.so.1.60.0
/usr/local/lib/libboost_wserialization_old_abi.so
/usr/local/lib/libboost_wserialization_old_abi.so.1.60.0
默认,主流Boost库正在像往常一样的/usr/lib
。会发生什么事是,当我任何一段代码链接到这些特定的库与自定义标记-lboost_system_old_abi
和-lboost_serialization_old_abi
,生成的二进制文件将被链接到默认Boost库:
$ ldd darwin_socket
linux-vdso.so.1 (0x00007ffd137ea000)
/usr/local/webots/resources/projects/robots/darwin-op/libraries/darwin/libdarwin.so (0x00007fcb9edaa000)
libipsocket.so.1 => /usr/local/lib/libipsocket.so.1 (0x00007fcb9eb7b000)
libboost_system.so.1.60.0 => /usr/lib/libboost_system.so.1.60.0 (0x00007fcb9e977000)
libboost_serialization.so.1.60.0 => /usr/lib/libboost_serialization.so.1.60.0 (0x00007fcb9e739000)
libController.so => not found
libCppController.so => not found
libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0x00007fcb9e3b7000)
libm.so.6 => /usr/lib/libm.so.6 (0x00007fcb9e0b2000)
libgcc_s.so.1 => /usr/lib/libgcc_s.so.1 (0x00007fcb9de9c000)
libc.so.6 => /usr/lib/libc.so.6 (0x00007fcb9dafb000)
/lib64/ld-linux-x86-64.so.2 (0x00007fcb9efc1000)
librt.so.1 => /usr/lib/librt.so.1 (0x00007fcb9d8f3000)
libpthread.so.0 => /usr/lib/libpthread.so.0 (0x00007fcb9d6d6000)
这是很奇怪的,因为如果使用原始的-lboost_system
和-lboost_serialization
标志,由于新旧ABI不兼容,gcc甚至无法链接到默认提升。
那么究竟发生了什么?